Prof. Köhler in ARD Sportschau on "RED-S - the creeping danger?"

Prof. Dr. Karsten Köhler spoke as an expert in the Sportschau report on Red-S syndrome
The Red-S syndrome results from low energy availability as a result of overtraining and a negative caloric balance

Prof. Dr. Karsten Köhler, head of the Assistant Professorship of Exercise, Nutrition and Health, was featured in a Sportschau report on ARD on November 7. Under the title "RED-S - the creeping danger?", the nutritionist commented on the "relative energy deficit in sports" (RED-S), which results from low energy availability as a consequence of overtraining and a negative calorie balance. He was also featured in a Nov. 12 radio segment on rbb Inforadio titled "The Red-S Syndrome".

"RED-S is a syndrome that we observe in athletes who, in order to be able to cover all bodily functions, do not have enough energy available," said Prof. Köhler. "That is, in normal cases, we see that people train a lot and don't get enough energy from food in a relatively measured way to do that."

So the causes of RED-S are too much training and a relatively low energy intake. An eating disorder can be just one of many symptoms; lack of drive or even depression are also conceivable consequences.

Prof. Köhler sees an underestimated danger in the syndrome and fears that there is a certain number of unreported cases here: "In general, figures of between 20 and 30 percent are estimated, which I consider realistic, and up to 60 percent in high-risk sports."

In the Sportschau report, professional triathlete Lea Sophie Keim, amateur triathlete Anja Kern and marathon runner and Olympic participant Deborah Schöneborn also comment on their experiences with RED-S. Anja Kern even reached a mental low with the syndrome. "In the end, I was really suicidal because I no longer saw any perspective, and because I didn't know what the reasons for the deep lethargy were. I didn't put those together with RED-S, not at all," Kern explains. The consequences of the syndrome can be irreparable, and women can even become infertile as a result of RED-S.

The former duathlon world champion and current coach Simon Hoyden criticizes the treatment of athletes: "Certainly the most blatant were the last years in my athletics career, when I heard that a coach - now in position national coach - said to younger women: You have to lose weight to get faster. That just can't be."

Based on such examples, Prof. Köhler also sees an urgent need for action: "If we don't get a grip on the problem - and do so systematically - then there will always be athletes who fall through the cracks, who are chronically injured and can't call up their performance and who, in case of doubt, will then also have to end their careers."

The German Olympic Sports Confederation told ARD Sportschau that it was continuously looking at the current state of research. The DOSB would support concrete measures in the event of reported suspicious cases by the state associations.


To the TV report „RED-S – the creeping danger?“ in ARD Sportschau

To the radio report „The RED-S-Syndrom“ of rbb Inforadio

To the homepage of the Assistant Professorship of Exercise, Nutrition and Health



Prof. Dr. Karsten Köhler
Assistant Professorship of Exercise, Nutrition and Health
Georg-Brauchle-Ring 60/62
80992 München

phone: 089 289 24488
e-mail: karsten.koehler(at)


Text: Romy Schwaiger
Photos: „ARD Sportschau“